Cathode Biased tone?

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mdroberts1243
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Cathode Biased tone?

Post by mdroberts1243 »

Maybe a dumb question, but I see sooo many differing opinions, I'd like the Dumble forum to weigh in on this...

How much 'tone' is attributed to the fixed bias output stages I see on the Dumble schematics? What about cathode biased as an alternative? What should I expect to be different in the sound?

Thanks,
-mark.
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Funkalicousgroove
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Re: Cathode Biased tone?

Post by Funkalicousgroove »

try it and see!
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Re: Cathode Biased tone?

Post by mlp-mx6 »

FYI - The Fuchs ODS 30W uses cathode bias.
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mdroberts1243
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Re: Cathode Biased tone?

Post by mdroberts1243 »

Funkalicousgroove wrote:try it and see!
I will be glad to do that, eventually. So far I've been building single-ended ultralinear amps and tube distortion pedals... I haven't yet got a push-pull platform to try it on. I'm gearing up for a PP build, and I think I've got a taste for the D'Lite design... but opinions and experience are quite appreciated well in advance!

Thanks,
-mark.
My tube blog & link directory: http://tubenexus.com
Cause & Effect Pedals FET Dream and Dumble Style Chassis
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heisthl
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Re: Cathode Biased tone?

Post by heisthl »

Cathode bias warms up the sound of normal Fender type amps but is not needed on clone builds. I had a switchable one one the first clone project that I later removed and I've never looked back. The tone is in the preamp - the output section should be as clean as possible. If you must try one here's a good switchable one to copy (Custom shop version of the Prosonic):
http://www.schematicheaven.com/fenderamps/prosonic.pdf
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mdroberts1243
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Re: Cathode Biased tone?

Post by mdroberts1243 »

heisthl wrote:Cathode bias warms up the sound of normal Fender type amps but is not needed on clone builds. I had a switchable one one the first clone project that I later removed and I've never looked back. The tone is in the preamp - the output section should be as clean as possible. If you must try one here's a good switchable one to copy (Custom shop version of the Prosonic):
http://www.schematicheaven.com/fenderamps/prosonic.pdf
Thanks Heisthl,
One of the 'touted' benefits of cathode biased is improvement in touch sensitivity... did you notice any differences there?
-mark.
My tube blog & link directory: http://tubenexus.com
Cause & Effect Pedals FET Dream and Dumble Style Chassis
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heisthl
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Re: Cathode Biased tone?

Post by heisthl »

I've yet to build a HRM clone but the non-HRM is definitly not lacking in touch sensitivity. I would say that the stock Prosonic I have is slightly more touch resposive on that position, but the biggest benifit for that amp is the improved tone (sounds warmer).
Former owner of Music Mechanix
www.RedPlateAmps.com
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